Leyla Parra-Almuna1,2, Sofía Pontigo1, Giovanni Larama3, Jonathan R Cumming4, Jacob Pérez-Tienda5, Nuria Ferrol5, María de la Luz Mora6. 1. Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Technological Bioresource Nucleus (BIOREN), Universidad de La Frontera, Avenida Francisco Salazar 01145, P.O. Box 54-D, Temuco, Chile. 2. Programa de Doctorado en Ciencias de Recursos Naturales, Universidad de La Frontera, Avenida Francisco Salazar 01145, P.O. Box 54-D, Temuco, Chile. 3. Centro de Excelencia de Modelación y Computación Científica, Universidad de La Frontera, Avenida Francisco Salazar 01145, P.O. Box 54-D, Temuco, Chile. 4. Department of Biology, West Virginia University, Morgantown, WV, 26506, USA. 5. Departamento de Microbiología del Suelo y Sistemas Simbióticos, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (EEZ-CSIC), Profesor Albareda 1, 18008, Granada, Spain. 6. Center of Plant, Soil Interaction and Natural Resources Biotechnology, Scientific and Technological Bioresource Nucleus (BIOREN), Universidad de La Frontera, Avenida Francisco Salazar 01145, P.O. Box 54-D, Temuco, Chile. mariluz.mora@ufrontera.cl.
Abstract
MAIN CONCLUSION: The phosphate transporters LpPHT1;1 and LpPHT1;4 have different roles in phosphate uptake and translocation in ryegrass under P stress condition. The phosphate transporter 1 (PHT1) family are integral membrane proteins that operate in phosphate uptake, distribution and remobilization within plants. In this study, we report on the functional characterization and expression of two PHT1 family members from ryegrass plants (Lolium perenne L.) and determine their roles in the specificity of Pi transport. The expression level of LpPHT1;4 was strongly influenced by phosphorus (P) status, being higher under P-starvation condition. In contrast, the expression level of LpPHT1;1 was not correlated with P supply. Yeast mutant complementation assays showed that LpPHT1;4 can complement the growth defect of the yeast mutant Δpho84 under Pi-deficient conditions, whereas the yeast mutant expressing LpPHT1;1 was not able to restore growth. Phylogenetic and molecular analyses indicated high sequence similarity to previously identified PHT1s from other species in the Poaceae. These results suggest that LpPHT1;1 may function as a low-affinity Pi transporter, whereas LpPHT1;4 could acts as a high-affinity Pi transporter to maintain Pi homeostasis under stress conditions in ryegrass plants. This study will form the basis for the long-term goal of improving the phosphate use efficiency of ryegrass plants.
MAIN CONCLUSION: The phosphate transporters LpPHT1;1 and LpPHT1;4 have different roles in phosphate uptake and translocation in ryegrass under P stress condition. The phosphate transporter 1 (PHT1) family are integral membrane proteins that operate in phosphate uptake, distribution and remobilization within plants. In this study, we report on the functional characterization and expression of two PHT1 family members from ryegrass plants (Lolium perenne L.) and determine their roles in the specificity of Pi transport. The expression level of LpPHT1;4 was strongly influenced by phosphorus (P) status, being higher under P-starvation condition. In contrast, the expression level of LpPHT1;1 was not correlated with P supply. Yeast mutant complementation assays showed that LpPHT1;4 can complement the growth defect of the yeast mutant Δpho84 under Pi-deficient conditions, whereas the yeast mutant expressing LpPHT1;1 was not able to restore growth. Phylogenetic and molecular analyses indicated high sequence similarity to previously identified PHT1s from other species in the Poaceae. These results suggest that LpPHT1;1 may function as a low-affinity Pi transporter, whereas LpPHT1;4 could acts as a high-affinity Pi transporter to maintain Pi homeostasis under stress conditions in ryegrass plants. This study will form the basis for the long-term goal of improving the phosphate use efficiency of ryegrass plants.
Authors: Alison Baker; S Antony Ceasar; Antony J Palmer; Jaimie B Paterson; Wanjun Qi; Stephen P Muench; Stephen A Baldwin Journal: J Exp Bot Date: 2015-05-04 Impact factor: 6.992
Authors: Bjørn P Pedersen; Hemant Kumar; Andrew B Waight; Aaron J Risenmay; Zygy Roe-Zurz; Bryant H Chau; Avner Schlessinger; Massimiliano Bonomi; William Harries; Andrej Sali; Atul K Johri; Robert M Stroud Journal: Nature Date: 2013-03-31 Impact factor: 49.962